Such a press roller normally has a roller core and a roller sleeve secured to the outer surface of the roller core and formed by a plurality of segments distributed over the outer surface with confronting side faces, the segments having clamping shoulders on their end faces with first clamping faces and the segments being secured detachably on the end face with at least one respective fastening ring to the roller core that engages over the clamping shoulders of the segments. It is preferably a press roller for a roller press for hot-briquetting or hot-compacting, for example hot-briquetting or hot-compacting of directly reduced iron (DRI). According to the invention, granular material also refers to dust or powder. The (bilateral) side faces are surfaces that delimit the respective segment in the circumferential direction. The side faces of a segment consequently angularly confront side faces of segments that are angularly adjacent and that extend axially, and they are clamped axially and radially and delimited by the inner surface and the outer surface of the segment.
A roller press generally has counterrotating two press rollers. During briquetting or compacting, granular bulk material is compacted between the rollers. To this end, the roller sleeve formed by the segments is equipped with pressing tools that can have cavities for the briquetting or compacting. However, the invention also includes press rollers with segments that are provided with another wear protection layer, for example for the comminuting material. Particularly during hot briquetting or hot compacting, the press rollers are exposed to high temperatures from the material to be processed, so that the segments themselves also reach high temperatures. This applies, for example, to the processing of reduced iron ores or sponge iron, in which the temperatures can reach up to 900° C. At high temperatures, the segments and their pressing tools are generally subjected to wear. In order to limit wear, such press rollers and their casings are generally cooled, for example by water. It has long since been known to integrate cooling passages into the clamping rings of the rollers.
Since the (tool) segments are generally subject to wear, they are detachably and thus exchangeably secured to the roller core. The fastening is done with by bilateral fastening rings that are also referred to as locking or clamping rings and that engage over the bilateral clamping shoulders of the segments. High demands are placed on the stability of these segments in practice, since they are subjected to high loads.
A roller press for hot compacting and hot briquetting bulk materials with press rollers with segments is known, for example, from DE 25 36 670 [U.S. Pat. No. 4,123,971]. The segments are provided with lugs or shoulders on which fasteners engage that secure the segments to the roller core. In this prior-art design, clamping brackets supported on the roller core are provided as fasteners that are pressed against the segment by a tension bolt. Alternatively, cooled shrink rings, radially arranged screws or the like are also proposed as fasteners.
The fastening of the segments by fastening rings or clamping rings that engage over the clamping shoulders of the segments is also known in practice. The clamping shoulders generally have the same cross section over the entire angular extent of the segment. The clamping bolts are provided at the region of the side faces between two mutually adjacent segments. To this end, suitable grooves are worked into the side faces to receive the clamping bolts. The known designs have proven themselves in principle, but they can be further developed with respect to their stability and durability. This is where the invention comes in.